#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>
int main() {
	int arr1[9] = { 1,2,3,4,5,1,2,3,4 };
	int arr3[10] = {0,1,2,3,4,5,6,7,8,9 };
	int arr2[10] = { 0 };
	for (int i = 0; i < 9; i++) {
		arr2[arr1[i]]++;
	}
	for (int i = 0; i < 9; i++) {
		if (arr2[i] == 1) {
			printf("%d", arr3[i]);
		}
		/*printf("%d", arr2[i]);*/
	}
	return 0;
}